You need something like Code Downloader (to download the cheats) and WiiCM (to put the ones you want into a format ocarina understands), both available through the Homebrew Browser. Hope that helps. Sorry I can't help more, but I don't cheat.

Most people won't, only sad f£$cks who have to win at all costs seem to, and hey, Ninty will ban them while they blame homebrew and not there own actions so let them cheat and whinge. I've ended up first in quite a few races I deserved to loose because of cheats been kicked so again, f£$ck them and let them get banned.